Most laboratory mice don't live long enough to go bald or grey, but a strain of animals missing an enzyme linked to cellular aging look like they could use a bit of Clairol or Rogaine. (sciencemag.org)
I had no way of knowing early on that my renaissance girl had Sensory Processing Disorder which was strongly affecting her ability to eat or that my little caboose was missing an enzyme and couldn't eat meat. (littleheartsbooks.com)
Missing an enzyme that helps break down food? (sciencemag.org)